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Took out 4 sunroof firewalls, cut off baffle and added zip tie, but still leaks
Hi, on a 2011 G37 coupe, I previously had a soaked rear floor board, only on the right side. I asked on the forums and the suggested route was to check out the right passenger firewall as it may have caused the water to flow to the back, although it didn't really make sense since my right passenger floor was not wet (https://streamable.com/v3f40r). Nevertheless, I checked it out and it had a few dirt trapped, so I cut off the baffle and put it back in. However, the next day, it turned out that both right passenger and rear floors are leaking. I also noticed that some water spots were left on the covering of the BCM (uh oh). I then thought it should be my right rear firewall. I did some research, and then changed that out, but it did not have a single clog. I was confused, and then it turns out that the left rear one had a clog
I got happy as I thought that it might've solved my problem because maybe the water route in the left rear was getting clogged so it sent out the remaining water to the right rear, hence my overflooverflowing. I noticed that there was some water underneath the carpet on the left side of the car (driver and rear), but not a significant amount from what I could see. Well, I then went to check out the driver plug and there wasn't a clog in it, but I snipped out the baffle just in case.
Fast forward to the next couple of days, and now I notice that there is water underneath my driver and passenger carpets along with water ABOVE the floor of my left rear carpet, while my right rear (the only one that was overflooding), was extremely dry with no water spots. Now I'm like befuddled because there shouldn't be a clog in the firewall because I removed the baffle. Could there be a clog in the drain tubes? How could I know which tube is being clogged? Also, when the water exits the car on the bottom, is it supposed to pour out very freely (as if you're pouring water from a tilting water bottle onto a cup) or is it able to go in clumps? Should I try blowing compressed air from the top of the sunroof first? Thank you all for your suggestions!
I followed the trick which is to insert a plastic straw and have it protrude 1-2 inches past the firewall grommets so water clears the initial hole.
I still have a leak but many have suggested that after you tackle the drains and it is still leaking then the sunroof pan gasket that seals the belly of the sunroof to the roof has broken and it will simulate a sunroof drain leak.
My leak comes from the same side as the drains but drains through the A pillar instead of the bottom from the drain. I also hear the roof assembly making flexing noises when I drive through inclines and declines.
I followed the trick which is to insert a plastic straw and have it protrude 1-2 inches past the firewall grommets so water clears the initial hole.
I still have a leak but many have suggested that after you tackle the drains and it is still leaking then the sunroof pan gasket that seals the belly of the sunroof to the roof has broken and it will simulate a sunroof drain leak.
My leak comes from the same side as the drains but drains through the A pillar instead of the bottom from the drain. I also hear the roof assembly making flexing noises when I drive through inclines and declines.
For the straw trick, what really does it serve versus just leaving it open (I didn't really understand what you meant when you said that "water clears the initial hole")? For the sunroof assembly, wouldn't the water like just drip on to the car's center console? Also, thanks for taking the time to read.
Unfortunately, it's hard to find cars that I otherwise like without a sunroof.
This my first car with a sunroof and funny enough, when I was looking for a G37 I wanted one with the sunroof (as a substitute for not finding a vert). Oh rip
For the straw trick, what really does it serve versus just leaving it open (I didn't really understand what you meant when you said that "water clears the initial hole")? For the sunroof assembly, wouldn't the water like just drip on to the car's center console? Also, thanks for taking the time to read.
The straw moves the drip point father away from the grommet. The desing for the grommet is flawed as the drops can travel backwards towards the gasket and if your gasket is messed up which most are or end up then you will leak.
The straw ends up moving the drip point farther into the body not letting it drip back. I feel you might be dealing with drains and roof pan problems.
The straw moves the drip point father away from the grommet. The desing for the grommet is flawed as the drops can travel backwards towards the gasket and if your gasket is messed up which most are or end up then you will leak.
The straw ends up moving the drip point farther into the body not letting it drip back. I feel you might be dealing with drains and roof pan problems.
Oh I get you. Looks like I'll take them out (I wouldn't think that the rear firewalls need a straw too?) once again and install a straw. I'm not really aware of the roof pan situation, so what do you recommend for me to do after installing the straws?
Didn't take very long... no guide either. Basically you need to just get a matching coupler and hose for the sunroof hose and just route it down into passenger floorboard, and T into the AC drain. you will see it once you peel up the carpet in that spot.
my driver side actually didn't leak so i left it alone, but you could do the same thing and just route it around I would think. Not sure there would be a floor drain on the driver side.
For the passenger side you will need:
- one (1) ⅜" barb coupling;
- one (1) ½" x ½" x ⅜" barb T-fitting;
- ⅜" ID tubing;
-5 zip ties (used as clanps).
I used brass fittings but you can use whichever material you prefer.
When you lift up the passenger carpet you will see the AC evaporator drain tube. It would not hurt to add a little silicone to the grommet where the tube passes through the floor.
I suggest you try you absolute most at tackling the flawed grommets first.
For the guys that relocated their drains, if this worked for you then it means that the problem lied in the actual body.
I know that the drains get clogged however this should then be the same case for the holes in where these grommets drain to. If this hole is clogged or full of dirt then it will leak.
I would fold the carpet and drive like that to monitor these leaks. This way you'll see where the drip is coming from, if it drips down the firewall it's your drains. If the leak falls on top of your left foot it might be coming from the top of the roof dripping down the pillar.
For the guys that relocated their drains, if this worked for you then it means that the problem lied in the actual body.
I must disagree. It is not a body issue. Whether it was/is the drain grommet or the tube is irrelevant. It is a inherently bad design which has a long history of failures to begin with.
Nissan should have extended the drain tubes through the firewalls down to the frame where it can harmlessly drip to the ground (just as the AC evaporator drains through the floor). Instead, water exits this grommet (which also acts as a choke point) and is free to migrate and go where it wants. Added to this is the fact that the main body harness grommet, which has it's own faults, lies directly in the drainage path.
Even with the "redesigned" grommet the chance exists for failure. The potential will always be there for water to drip onto the electronics and flood the floorpan. By rerouting the drain tubes, water from the sunroof drains goes straight the ground and does not have a chance to enter the cabin.
Everyone has their own solutions to this problem and we all have our own methods to madness.
10-26-2020, 12:48 PM
